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Appendix |EtherCAT Documentation
confocalDT 24x1
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Statistic maximum value Ethernet/EtherCAT
Statistical value (maximum)
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Statistic peak-peak value Ethernet/EtherCAT
Statistical value (peak to peak)
In EtherCAT the PDOs are transported in objects of the Sync Manager channel. The sen-
sor uses the Sync Manager channel SM3 for input data (Tx data). The PDO assignments
of the Sync Manager can only be changed in the “Pre-Operational” state. The map-
ping in the confocalDT 24x1 is not carried out directly in the object 0x1A00, but rather
by switching on and off individual measurements in the application object 0x21B0. The
mapping result is available to the master after reloading the object directory.
Note:
Subindex 0h of the object 0x1A00 contains the number of valid entries within
the mapping report. This number also represents the number of application variables
(parameters) that should be transmitted/received with the corresponding PDO. The
subindices from 1h up to the number of objects contain information about the depicted
application variables. The mapping values in the CANopen objects are coded in hexa-
decimal form.
The following table contains an example of the entry structure of the PDO mapping:
MSB
LSB
31
16 15
8 7
0
Index e.g. 0x6065
(16 bits)
Subindex e.g. 0x02
Object length in bits,
e.g. 20h = 32 bits
Fig. 84 Entry structure of the PDO mapping, example
A 6.1.8 Service Data SDO Service
Service Data Objects (SDOs) are primarily used for the transmission of data that are not
time critical, e.g. parameter values. EtherCAT specifies the SDO services as well as the
SDO information services: SDO services make possible the read/write access to entries
in the CoE object directory of the device. SDO information services make it possible to
read the object directory itself and to access the properties of the objects. All parameters
of the measuring device can be read or changed in this way, or measurements can be
transmitted. A desired parameter is addressed via index and subindex within the object
directory.